Question

题目内容

解题思路

栈。

代码实现

const isValid = (s: string): boolean => {
  type KeyType = ")" | "}" | "]";
  type ValueType = "(" | "{" | "[";
  const n: number = s.length;
  if (n % 2 === 1) return false;
  const mapObj: Record<KeyType, ValueType> = {
    ")": "(",
    "}": "{",
    "]": "[",
  };
  const stk: ValueType[] = [];
  for (let item of s) {
    if (item in mapObj) {
      let top = stk.pop();
      if (mapObj[item] !== top) {
        return false;
      }
    } else {
      stk.push(item as ValueType);
    }
  }
  return !stk.length;
};